Printing materials elevator

ABSTRACT

Installed in a rotary press which is provided with an upper work floor T and a lower work floor U to accommodate multi-layered printing sections, there are included upper turning bodies B installed at a high level on an upper story W, opposing each other at an interval larger than the width of a press plate P; lower turning bodies C installed at a low level on a lower story X, opposing the upper turning bodies B vertically and opposing each other at the same interval as the upper turning bodies B; endless flexible bodies D looped over the upper and lower turning bodies B and C; a drive unit E for rotating the turning bodies so as to run the endless flexible bodies D all at once; and a press plate holding F unit which has a plurality of press plate holders and which is disposed between the left and right endless flexible bodies D with its left and right sides connected to the rear or front segments of the respective endless flexible bodies D stretched between the upper turning bodies B and the lower turning bodies C.

FIELD OF THE INVENTION

[0001] The present invention relates to a printing materials elevatorused in a rotary press which consists of multi-layered printing sectionsneeding press plates and comprises an upper work floor corresponding tothe upper printing section and a lower work floor corresponding to thelower printing section, to transfer printing materials such as unused orused press plates and a print roller (roller for the printing sections)between the above described two work floors.

BACKGROUND OF THE INVENTION

[0002] Prior art relating to a printing materials elevator whichtransfers printing materials between an upper work floor and a lowerwork floor to accommodate multi-layered printing sections of a rotarypress is disclosed in Japanese Patent Publication No. 2762029.

[0003] The apparatus disclosed in Japanese Patent Publication No.2762029 is an apparatus for elevating press plates for multi-layeredprinting sections of a rotary press. It transfers press plates to theupper printing section and transfers used press plates from the upperprinting section.

[0004] The apparatus is equipped with two endless chains mountedvertically facing each other, and by driving them simultaneously viasprockets, it transfers press plates suspended from press plate hangersmounted between the endless chains.

[0005] Incidentally, there is no mention of print roller transfer.

[0006] With the prior art described above, i.e., the apparatus disclosedin Japanese Patent Publication No. 2762029, it requires time and laborto take out a desired press plate since press plates are suspended oneby one by the endless chains: the operator must start the chain drive tomake the chains travel and must stop them at a convenient place to takeout the desired press plate. Consequently, it is difficult to improvethe efficiency of press plate replacement in the upper printing section.

[0007] Besides, to transfer a print roller to the upper printingsection, the operator must generally carry the print roller manuallyfrom the lower printing section to the upper printing section or raisethe print roller by a chain block or electric hoist installed on theupper story. This is burdensome for the operator requiring skill fromthe operator, and involving risk.

[0008] Under these circumstances, there has been demand for a printingmaterials elevator which allows desired press plates to be transferredwithout much time and effort and can improve the efficiency of pressplate replacement in the above described printing section. Also, therehas been demand for a printing materials elevator which allows a printroller to be transferred easily without any risks.

SUMMARY AND OBJECTS OF THE INVENTION

[0009] An object of the present invention is to provide a printingmaterials elevator which allows desired press plates to be transferredwithout skill, much time and effort and can improve the efficiency ofpress plate replacement in the upper printing section.

[0010] Another object of the present invention is to provide a printingmaterials elevator which allows a print roller to be transferred easilyand can improve the efficiency of print roller replacement in the upperprinting section.

[0011] Another object of the present invention is to provide a printingmaterials elevator which allows a print roller to be transferred easilytogether with desired press plates and can improve the efficiency ofpress plate and print roller replacement in the upper printing section.

[0012] Another object of the present invention is to provide a printingmaterials elevator which is automatically stopped at a predeterminedstopping position.

[0013] Another object of the present invention is to provide a safeprinting materials elevator which makes it possible to transfer a printroller easily without being concerned about dropping the print rollerand reduce the burden on the operator.

[0014] Another object of the present invention is to provide press plateholding means which can contain an appropriate number of press platesaccording to their size.

[0015] Another object of the present invention is to provide simplystructured endless flexible bodies to which press plate holding meansand roller holding means can be easily mounted.

[0016] In the embodiment described below, the printing materialselevator A comprises upper turning bodies B, lower turning bodies C,endless flexible bodies D, drive means E, press plate holding means F,and roller holding means G and is configured such that the press platesand print roller in both upper and lower printing sections can be easilyreplaced.

[0017] The various features of novelty which characterize the inventionare pointed out with particularity in the claims annexed to and forminga part of this disclosure. For a better understanding of the invention,its operating advantages and specific objects attained by its uses,reference is made to the accompanying drawings and descriptive matter inwhich a preferred embodiment of the invention is illustrated.

BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In the drawings:

[0019]FIG. 1 is a perspective view showing a configuration of anembodiment of the present invention;

[0020]FIG. 2 is a sectional view along a line II-II in FIG. 1 showing amechanism, including endless flexible bodies, of a printing materialselevator shown in FIG. 1;

[0021]FIG. 3 is a sectional view along a line III-III in FIG. 1 showingpress plate holding means of the printing materials elevator shown inFIG. 1;

[0022]FIG. 4 is a sectional view along a line IV-IV in FIG. 1 showingroller holding means of the printing materials elevator shown in FIG. 1;

[0023]FIG. 5 is an operational side view showing an operation of thedrive means of the printing materials elevator shown in FIG. 1; and

[0024]FIG. 6 is a lateral block diagram showing an outline of a rotarypress in which the printing materials elevator shown in FIG. 1 isimplemented.

DESCRIPTION OF THE PREFERRED EMBODIMENT

[0025] Referring to FIGS. 1 to 6, a rotary press V shown in FIG. 6consists of multi-layered printing sections S (upper printing section STand lower printing section SU) needing laminated press plates P (seeFIGS. 1 and 2), comprises an upper work floor T corresponding to theupper printing section ST and a lower work floor U corresponding to thelower printing section SU, and divides its available space into an upperstory W providing a workspace on the upper work floor T and a lowerstory X providing a workspace on the lower work floor U.

[0026] A printing materials elevator A is provided to transfer pressplates P and a roller R (see FIG. 4), already used or to be used in theupper printing section ST, between the upper story W and lower story Xof the rotary press V.

[0027] The printing materials elevator A of the present invention isinstalled, for example, between opposed frames 23 and 24 provided on theupper story W and lower story X, passing through the hole 25 made in theupper work floor T of the upper story W, as shown in FIG. 1.

[0028] That side of the printing materials elevator A which faces theprinting sections S (upper printing section ST and lower printingsection SU) constitutes a working side from which the press plates Pused on printing cylinders Q in the printing section ST and the printroller R to be replaced are inserted into or taken out of the printingmaterials elevator A and where the front segments of left and rightendless flexible bodies D described later are designed to travel.(Hereinafter, the working side will be referred to as the front side 28and the other side of printing materials elevator A will be referred toas the rear side 29.)

[0029] The printing materials elevator A of the present inventioncomprises upper turning bodies B, lower turning bodies C, endlessflexible bodies D, drive means E, press plate holding means F, androller holding means G, each of which will be described below.

[0030] 1. Upper Turning Bodies B

[0031] As shown in FIG. 1, a horizontal shaft 1 is rotatably supportedbetween the frames 23 and 24 at a high level (e.g., a level higher thanthe head of the operator) on the upper story W.

[0032] A sprocket 2 and sprocket 3 of an equal outside diameter, whichare the left upper turning body and the right upper turning body,respectively, are installed on the shaft 1, opposing each other in theaxial direction of the shaft 1, at an interval larger than the width ofthe press plate P

[0033] 2. Lower Turning Bodies C

[0034] As shown in FIG. 1, a shaft 4, parallel to and verticallyopposite the shaft 1 of the upper turning bodies B, is rotatablysupported between the frames 23 and 24 at a low level (e.g., a levelapproximately corresponding to the knees of the operator) on the lowerstory X.

[0035] A sprocket 5 and sprocket 6, which are the left lower turningbody and the right lower turning body, respectively, and which are equalin outside diameter to and vertically opposite the sprockets 2 and 3 ofthe upper turning bodies B, are installed in the axial direction of theshaft 4.

[0036] 3. Endless Flexible Bodies D

[0037] These are a left endless flexible body D consisting of a chain 7and a right endless flexible body D consisting of a chain 8, shown inFIGS. 1 and 2. The chain 7 is looped over the sprocket 2 of the upperturning body B and the sprocket 5 of the lower turning body C. The chain8 is looped over the sprocket 3 of the upper turning body B and thesprocket 6 of the lower turning body C.

[0038] The chains 7 and 8 are roller chains consisting of rollersrotatably attached to the link pins of the chains.

[0039] Chain guides 9 and 10 are installed along those segments of thechains 7 and 8 which travel linearly up and down (vertically):specifically, the chain guides 9 are installed along a front chainsegment 7 a and rear chain segment 7 b of the left endless flexible bodyand the chain guides 10 are installed along a front chain segment 8 aand rear chain segment 8 b of the right endless flexible body.

[0040] Each of the chain guides 9 and 10 is a pair of long, narrowplates which sandwich the rollers of the chains 7 or 8 from both sideswith small gaps provided.

[0041] Legs of the chain guides 9 and 10 are attached to the mutuallyopposing flanks of the frames 23 and 24.

[0042] This restricts the movements of the chain segments 7 a, 7 b, 8 a,and 8 b except their up-and-down (vertical) movement.

[0043] Links 27 with an attachment, which is a link plate extended toform a letter L and protrude like a tongue, are used in the chainsegments 7 a, 7 b, 8 a, and 8 b where press plate holding means F orroller holding means G described later are attached.

[0044] 4. Drive Means E

[0045] As shown in FIG. 1, a motor 11 is installed on the lower workfloor U under the lower turning bodies C. The shaft of the motor 11 isfitted with a sprocket 12, whose counterpart, sprocket 14, is fittedover the shaft 4 fitted with the lower turning bodies C. A chain 13 islooped over the sprockets 12 and 14.

[0046] The motor 11 starts when a start button on a control panelinstalled at an appropriate location is pressed. It stops in response toa detection signal from detectors such as proximity switches installedat appropriate locations on the frames 23 and 24 near the chains 7 and 8of the endless flexible bodies D when the detectors detect detectableelements on the chains 7 and 8 at predetermined stopping locations ofthe chains 7 and 8. This causes the press plate holding means F orroller holding means G installed on the chains 7 and 8 of the endlessflexible bodies D to stop at working height Y (described later) on theupper story W and lower story X so that the chains 7 and 8 travel up anddown.

[0047] 5. Press Plate Holding Means F

[0048] The press plate holding means F shown in FIGS. 1 and 3 consistsof stacked racks 15, which are press plate holders for holding pressplates P.

[0049] The press plate P is a rectangular sheet, one of whose longersides is provided with a bent portion Pa formed by folding a narrow bendallowance at an acute angle (see FIG. 3).

[0050] As shown in FIG. 2, the rack 15, installed between the frames 23and 24, consists of long, narrow shelf boards 15 a arranged at lateralintervals with their length extending from the front side 28 to the rearside 29, long, narrow brackets 15 b bridged across the underside of theshelf boards 15 a on the front and rear sides, and a bracket 15 b′bridged across the underside of the shelf boards 15 a in the center,forming a lattice.

[0051] The bracket 15 b′ bridged across the length of the shelf boards15 a in the center has both its ends protruded longer toward the frames23 and 24 than the brackets 15 b. Furthermore, both ends are attached toone end each of brackets 16 and 17, whose other ends are connected tothe links 27 with the attachment installed on the chain segment 7 b or 8b of the endless flexible body D (see FIGS. 2 and 3).

[0052] The racks 15 are connected to the respective links 27 with theattachment, which are mounted consecutively for a certain interval onthe chain segments 7 b and 8 b.

[0053] A connecting plate 15 c is attached to the center of theunderside of the brackets 15 b and 15 b′, in parallel to the length ofthe shelf boards 15 a. The connecting plates 15 c connect each of thestacked racks 15 with the vertically adjacent rack and partition eachrack 15 into right and left halves.

[0054] In the front side 28 of the press plate holding means F, the rack15 has inlets 30 through which press plates P can be taken in and out,and the shelf boards 15 a of the rack 15 are installed at an angle suchthat the inlets 30 face obliquely upward. Consequently, the press plateholding means F consisting of the racks 15 has an approximatelyparallelogram profile on the sides facing the chain 7 or 8, as shown inFIG. 3.

[0055] The tilt angle of the shelf boards 15 a is set approximatelyequal to the complementary angle of the acute angle of the bent portionPa of the press plate P.

[0056] The racks 15 are supported between the chain segments 7 b and 8 band driven by the drive means E. They are installed such that when thechain 7 and 8 travel, there will be no interference between the pressplate holding means F and the edge of the hole 25 made in the abovedescribed upper work floor T, between the roller holding means Gdescribed below (if attached to the chain segments 7 a and 8 a) and theedge of the hole 25 in the upper work floor T, or between the pressplate holding means F and roller holding means G.

[0057] Although according to the embodiment of the present invention,the press plate holding means F have two columns of inlets 30 with theconnecting plates 15 c installed in the center so that each of the racks15 will contain two press plates P as shown in FIG. 1, it is possible tochange the design and install the connecting plates 15 c on the rightand left sides according to the size of the press plate P so that eachof the racks 15 will contain one press plate P.

[0058] 6. Roller Holding Means G

[0059] The roller holding means G shown in FIG. 1 is installed on thechain segments 7 a and 8 a of the endless flexible bodies D.

[0060] The roller holding means G is installed on the chain segments 7 aand 8 a, for example, such that the roller holding means G will belocated at the working height Y on the lower story X when the pressplate holding means F installed on the chain segments 7 b and 8 b stopsat the working height (for example, a height between the chest and waistof the operator, i.e., height from the floor convenient for the operatorto mount and dismount press plates P and a print roller R to/from therespective holding means F and G) Y on the upper story W and that theroller holding means G will be located at the working height Y on theupper story W when the press plate holding means F stops at the workingheight Y on the lower story X (see FIGS. 5A and 5B).

[0061] The roller holding means G shown in FIGS. 2 and 4 consists ofL-shaped arms 18 and 19, one end each of which is connected to the link27 (equipped with the attachment) installed on the chain segment 7 a or8 a of the endless flexible body D. The lower parts of the L-shaped arms18 and 19 protrude almost horizontally in the direction opposite to thechain segments 7 b and 8 b.

[0062] Rollers 18 a and 19 a are rotatably supported by respectiveshafts 18 b and 19 b on the flanks of the bent portions of the L-shapedarms 18 and 19. The peripheries of the rollers 18 a and 19 a are incontact with the flanks of the chain guides 9 and 10 for the chainsegments 7 b and 8 b.

[0063] The ends of a connecting rod 20 are connected, respectively, tothe ends of the protruding portions of the arms 18 and 19 to unite thearms 18 and 19.

[0064] Spaced from the arms 18 and 19, respectively, hooks 21 and 22 forholding the print roller R, or roller holders are installed on theconnecting rod 20. The bases of the hooks 21 and 22 are rotatably fittedin the connecting rod 20, leaving a space suitable for supportingjournals on both ends of the print roller R.

[0065] The hooks 21 and 22 are installed in such a way that both flanksof their bases are pinched by collars (not shown) mounted on theconnecting rod 20 so that the hooks 21 and 22 will not move in the axialdirection of the connecting rod 20.

[0066] As shown in FIG. 4, bars 21 a and 22 a are mounted on sides ofthe hooks 21 and 22, serving as stoppers to prevent the journals of theprint roller R held by the hooks 21 and 22 from coming off.

[0067] A protector 26 is attached to the center of the horizontalprotrusion of each arm 18 or 19. The protectors 26, which are shapedlike a letter L extending to just under the print roller R supported bythe hooks 21 and 22, protect the underside of the print roller R. Theyare provided with a catch to prevent the print roller R from fallingshould the journals of the print roller R come off the hooks 21 and 22.

[0068] As shown in FIG. 2, the arms 18 and 19 are spaced wider than therack 15 of the press plate holding means F and the protectors 26 areattached to the arms 18 and 19 at some distance away from the inlets 30of the press plate holding means F. This prevents interference betweenthe press plate holding means F and roller holding means G as well asbetween the roller holding means G and the edge of the hole 25 in theupper work floor T when the chains 7 and 8 travel, being driven by thedrive means E.

[0069] As shown in FIG. 4, the weight of the print roller R held by thehooks 21 and 22 acts on the chain guides 9 and 10 via the rollers 18 aand 19 a mounted on the arms 18 and 19 with the ends of the arms 18 and19 connected to the links 27 (equipped with the attachment) serving asfulcrums. Since the rollers 18 a and 19 a travel in rolling contact withthe chain guides 9 and 10, the print roller R can be held andtransferred in a stable manner during vertical travel of the chainsegments 7 a and 8 a.

[0070] Now the operation of the printing materials elevator A will bedescribed with reference to FIGS. 5A and 5B.

[0071] Referring to FIG. 5A, the press plate holding means F and rollerholding means G are at halt in a stand-by state, at the working height Yon the lower story X and upper story W, respectively. The press plateholding means F is holding, for example, the press plates P to be usedin the upper printing section ST on the upper story W while the rollerholding means G is holding, for example, the used print roller Rreplaced in the upper printing section ST on the upper story W.

[0072] In this state, the operator starts the drive means E by pressinga start button on a control panel installed at an appropriate location.

[0073] Then the shaft of the motor 11 shown in FIG. 5A rotatesclockwise, causing the chains 7 and 8 or the endless flexible bodies Dto travel, which in turn causes the press plate holding means F on thelower story X to move up and the roller holding means G on the upperstory W to move down.

[0074] Referring to FIG. 5B, when the ascending press plate holdingmeans F reaches the working height Y on the upper story W and thedescending roller holding means G reaches the working height Y on thelower story X, the detectors detect the detectable elements on thechains 7 and 8 and the motor 11 of the drive means E stops rotation inresponse to the detection signal, putting the apparatus in the stand-bystate.

[0075] Consequently, the press plates P to be used in the upper printingsection ST is transferred to the upper story W and the used print rollerR replaced in the upper printing section ST on the upper story W istransferred to the lower story X.

[0076] The sequence of operations described above transfers the pressplates P and print roller R in the printing materials elevator A of arotary press in which the printing sections S (upper printing section STand lower printing section SU) are installed in two tiers and which hasthe upper work floor T corresponding to the upper printing section STand the lower work floor U corresponding to the lower printing sectionSU.

[0077] Although the printing materials elevator A described abovecomprises both press plate holding means F and roller holding means G,it is also possible to configure the printing materials elevator A tohave only press plate holding means F or roller holding means G.

[0078] As described above, according to the present invention, sincepress plates are held in stacks, required press plates can betransferred all at once without much time and effort. Furthermore, sincepress plates are held by the press plate holding means at a slant andtaken in and out of the press plate holding means along the slant, theoperator can handle press plates easily and reliably without any need,for example, to support any sag in the middle of the press plates, whichis the case when taking them horizontally in and out of press plateholding means. This improves the efficiency of work and eventually theefficiency of press plate replacement.

[0079] Also, since the print roller is transferred, being heldhorizontally in a stable manner, the operator can transfer it easilywithout being concerned about dropping it. This reduces the operator'sburden as well as danger.

[0080] While specific embodiments of the invention have been shown anddescribed in detail to illustrate the application of the principles ofthe invention, it will be understood that the invention may be embodiedotherwise without departing from such principles.

What is claimed is:
 1. A printing materials elevator used in a rotarypress which consists of multi-layered printing sections and which has anupper work floor corresponding to an upper printing section for raisingand lowering printing materials as well as a lower work floorcorresponding to a lower printing section, comprising: a left upperturning body and a right upper turning body installed at a high level onan upper story containing the upper work floor, opposing each other atan interval larger than the width of a press plate; a left lower turningbody and a right lower turning body installed at a low level on a lowerstory containing the lower work floor, opposing the upper turning bodiesvertically and opposing each other at the same interval as the upperturning bodies; a left endless flexible body looped over the left upperand lower turning bodies and a right endless flexible body looped overthe right upper and lower turning bodies; drive means for rotating theturning bodies so as to run the left and right endless flexible bodiesall at once; and press plate holding means which has a plurality ofpress plate holders installed at an angle and at predetermined verticalintervals and which is disposed between the left and right endlessflexible bodies with its left and right sides connected to the rear orfront segments of the respective endless flexible bodies stretchedbetween the upper and lower turning bodies.
 2. A printing materialselevator used in a rotary press which consists of multi-layered printingsections and which has an upper work floor corresponding to an upperprinting section for raising and lowering printing materials as well asa lower work floor corresponding to a lower printing section,comprising: a left upper turning body and a right upper turning bodyinstalled at a high level on an upper story containing the upper workfloor, opposing each other at an interval larger than the width of apress plate; a left lower turning body and a right lower turning bodyinstalled at a low level on a lower story containing the lower workfloor, opposing the upper turning bodies vertically and opposing eachother at the same interval as the upper turning bodies; a left endlessflexible body looped over the left upper and lower turning bodies and aright endless flexible body looped over the right upper and lowerturning bodies; drive means for rotating the turning bodies so as to runthe left and right endless flexible bodies all at once; and rollerholding means wherein the left and right sides of roller holders whichcan hold a print roller are connected to the rear or front segments ofthe respective endless flexible bodies stretched between the upper andlower turning bodies.
 3. A printing materials elevator used in a rotarypress which consists of multi-layered printing sections and which has anupper work floor corresponding to an upper printing section and a lowerwork floor corresponding to a lower printing section, comprising: a leftupper turning body and a right upper turning body installed at a highlevel on an upper story containing the upper work floor, opposing eachother at an interval larger than the width of a press plate; a leftlower turning body and a right lower turning body installed at a lowlevel on a lower story containing the lower work floor, opposing theupper turning bodies vertically and opposing each other at the sameinterval as the upper turning bodies; a left endless flexible bodylooped over the left upper and lower turning bodies and a right endlessflexible body looped over the right upper and lower turning bodies;drive means for rotating the turning bodies so as to run the left andright endless flexible bodies all at once; and press plate holding meanswhich has a plurality of press plate holders installed at an angle andat predetermined vertical intervals and which is disposed between theleft and right endless flexible bodies with its left side connected tothe rear segment of the left endless flexible body stretched between theupper and lower turning bodies and its right side connected to the rearsegment of the right endless flexible body stretched between the upperand lower turning bodies; roller holding means wherein roller holderswhich can hold a print roller outside the travel area of the press plateholding means are connected to the front segments of the left and rightendless flexible bodies.
 4. The printing materials elevator according toclaim 1, wherein said press plate holding means constitutes stackedracks each having slanted shelf boards, and are configured to contain anappropriate number of press plates according to the size of the pressplates.
 5. The printing materials elevator according to claim 1, whereinsaid endless flexible bodies are chains and said press plate holdingmeans are attached to links which compose the chains and each of whichis equipped with an attachment extending to form a letter L and protrudelike a tongue.
 6. The printing materials elevator according to claim 2,wherein said endless flexible bodies are chains and said print rollerholding means are attached to links which compose the chains and each ofwhich is equipped with an attachment extending to form a letter L andprotrude like a tongue.
 7. The printing materials elevator according toclaim 2, wherein said print roller holding means is provided with asafety catcher to prevent the print roller from falling out of theapparatus.
 8. The printing materials elevator according to claim 1,wherein detectable elements are attached to said endless flexible bodiesand when detectors detect said detectable elements, said drive meansstops the endless flexible bodies at a predetermined position to stopthe press plate holding means and/or print roller holding means inplace.
 9. The printing materials elevator according to claim 1, whereina guard plate is installed along each of said endless flexible bodies.10. The printing materials elevator according to claim 3, wherein saidpress plate holding means constitutes stacked racks each having slantedshelf boards, and are configured to contain an appropriate number ofpress plates according to the size of the press plates.
 11. The printingmaterials elevator according to claim 3, wherein said endless flexiblebodies are chains and said press plate holding means are attached tolinks which compose the chains and each of which is equipped with anattachment extending to form a letter L and protrude like a tongue. 12.The printing materials elevator according to claim 3, wherein saidendless flexible bodies are chains and said print roller holding meansare attached to links which compose the chains and each of which isequipped with an attachment extending to form a letter L and protrudelike a tongue.
 13. The printing materials elevator according to claim 3,wherein said print roller holding means is provided with a safetycatcher to prevent the print roller from falling out of the apparatus.14. The printing materials elevator according to claim 2, whereindetectable elements are attached to said endless flexible bodies andwhen detectors detect said detectable elements, said drive means stopsthe endless flexible bodies at a predetermined position to stop thepress plate holding means and/or print roller holding means in place.15. The printing materials elevator according to claim 3, whereindetectable elements are attached to said endless flexible bodies andwhen detectors detect said detectable elements, said drive means stopsthe endless flexible bodies at a predetermined position to stop thepress plate holding means and/or print roller holding means in place.16. The printing materials elevator according to claim 2, wherein aguard plate is installed along each of said endless flexible bodies. 17.The printing materials elevator according to claim 3, wherein a guardplate is installed along each of said endless flexible bodies.